Multiple position, variable intensity lamp

ABSTRACT

In a floor lamp, a lamp receptacle which is universally pivoted to one end of a shaft is provided with a variable impedance circuit for controlling the intensity of luminance emitted by the lamp. The other end of the shaft is bifurcated and defines a pair of substantially equal and outwardly diverging legs which operate to engage the interior wall of a sleeve mounted to a base member. The engagement of the legs and interior wall of the sleeve defines a frictional lock which allows slidable and rotational movement of the shaft within the sleeve.

United States Patent Chapman, Jr. et al.

[451 Sept. 26, 1972 [54] MULTIPLE POSITION, VARIABLE INTENSITY LAMP [72]Inventors: Earle F. Chapman, Jr., Marshfield Hills; Bernard J. Ruskin,Marblehead, both of Pa.

[73] Assignee: Chapman Manufacturing Company,

Avon, Mass.

[22] Filed: Jan. 25, I971 211 Appl. No.: 109,140

[52] US. Cl. ..240/81 R, 248/168, 248/408, 248/41 1 [51] Int. Cl. ..F2ls1/12, F21s 3/10 [58] Field of Search.240/8l R, 81 BS, 81 BA, 81 BE,240/81 BC, 70, 67; 248/411, 408, 168

[56] References Cited UNlTED STATES PATENTS 2,642,246 6/ 1953 Stephans..240/81 R X lcove et a1 ..240/81 BS X Dubroff et al ..240/81 R XPrimary Examiner-Samuel S. Matthews Assistant Examiner-Richard A.Wintercorn At!0rney-Morse, Altman & Oates [57] ABSTRACT In a floor lamp,a lamp receptacle which is universally pivoted to one end of a shaft isprovided with a variable impedance circuit for controlling the intensityof luminance emitted by the lamp. The other end of the shaft isbifurcated and defines a pair of substantially equal and outwardlydiverging legs which operate to engage the interior wall of a sleevemounted to a base member. The engagement of the legs and interior wallof the sleeve defines a frictional lock which allows slidable androtational movement of the shaft within the sleeve.

8 Claims, 7 Drawing Figures PATENTEDSEP26|912 3.694.647

SHEET '1 or 2 INVENTORS s4 74 EARL F. CHAPMAN, JR.

BYBERNARD J. RUSKIN ATTORNEYS MULTIPLE POSITION, VARIABLE INTENSITY LAMPBACKGROUND OF THE INVENTION 1 Field of the Invention The inventionrelates to lamps and more particularly to a multiple position, variableintensity lamp.

2. Description of the Prior Art The intensity and orientation of a lightsource is of key importance in minimizing eye strain, especially when aperson is reading or studying for extended periods of time. Generally,floor lamps which are designed to be used as reading lamps have sufferedfrom the disadvantage that they provide only a limited degree ofadjustment with respect to both the orientation of the light source andthe intensity of the luminance.

SUMMARY OF THE INVENTION It is an object of the present invention toprovide a floor lamp having a relatively unlimited degree of adjustmentwith respect to both the orientation of the light source and theintensity of the luminance. The lamp is characterized by a universallymounted lamp receptacle, a variable impedance circuit, a hollow shaft, asleeve, and a base. The shaft is received within the sleeve which ismounted to the base. The periphery of the shaft, at one end thereof, issplit along the longitudinal axis into two substantially equal andoutwardly diverging legs which operate to engage the interior wall ofthe sleeve. The engagement of the legs and interior sleeve wall definesa frictional lock which allows slidable and rotational movement of theshaft within the sleeve upon the application of a slight force thereto.The intensity of luminance emitted from the lamp is controlled by thevariable impedance circuit which is mounted within the lamp receptacle.The combination of rotatable and slidable shaft, universally mountedlamp receptacle, and variable impedance circuit is such as to provide aversalite, multiple position, variable intensity lamp.

The invention accordingly comprises the lamp possessing theconstruction, combination of elements and arrangement of parts that areexemplified in the following detailed description, the scope of whichwill be indicated in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of thenature and objects of the present invention, reference should be had tothe following detailed description taken in connection with theaccompanying drawings, wherein:

FIG. 1 is a perspective of a lamp embodying the present invention;

FIG. 2 is a sectional taken along the lines 2-2 in FIG. 1;

FIG. 3 is a framentary side elevation, partly in section, illustratingcertain details of the lamp;

FIG. 4 is a perspective illustrating certain details of an alternativeembodiment of the invention;

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings, amultiple position, variable intensity lamp embodying the invention isshown in FIG. 1 at 10. Lamp comprises a circular base portion 12 whichis provided with an annular skirt 14. Base 12 is formed with aconcentric through hole 16 which is adapted to receive a sleeve 18having externally threaded ends 20, 22. An internally threaded ring 24having a knurled outer edge 26 and a fastener 28, for example a hexagonnut, are turned onto threaded end at opposed faces of base 12. Hole 16is slightly larger than threaded end 20 and smaller than ring 24 and nut28, whereby sleeve 18 is secured to base 12 by 5 the vise-like grip ofring 24 and nut 28 on the opposed FIG. 5 is a schematic diagram of thevariable imfaces of base 12. In an alternative embodiment, sleeve 18 isrotatably mounted to base 12 by means of a rotatable coupler (notshown). An internally threaded bushing 30 is turned onto threaded end22. Bushing 30 is provided with a concentric through hole 32 which isadapted to slidably receive a hollow bent shaft 34. A fabric washer 36is interposed between the edge of sleeve 18 and a shoulder 37 at theinterior face of bushing 30.

As best shown in FIG. 2, one end of shaft 34 is bifurcated and defines apair of substantially equal and outwardly diverging arcuate legs 36, 38which operate to engage the interior wall of sleeve 18. The engagementof legs 36, 38 and the interior wall of sleeve 18 defines a frictionallock. That is, shaft 34 is slidable and rotatable within sleeve 18 uponapplication of a force sufficient to overcome the friction between legs36, 38 and the interior wall of sleeve 18. The other end of shaft 34 isexternally threaded and a ball and socket fixture 39 is turned thereon.

It is to be understood that, in alternative embodiments, the end ofshaft 34 is other than bifurcated as shown in FIG. 4. In this case, asleeve 170, which corresponds to sleeve 18, is formed with an aperture172 which operates to receive a tapped insert 174. A fastener 176, forexample a locking screw having a knurled head 177 is turned into tappedinsert 174 until the end of screw 176 engages a shaft 178 whichcorresponds to shaft 34. In consequence, shaft 178 is locked withrespect to sleeve by screw 176.

As shown in FIG. 4, a base 180 which corresponds to base 12 includes aweighted stabilizing section 182 which is fixed to sleeve in a mannersimilar to that described for fastening sleeve 18 to base 12. Section182 includes a plurality of legs 184, for example three legs, which arearcuately distributed 120 from each other. Each leg 184 extends belowthe annular skirt portion of base and defines a supporting structure. Aline cord 186 having a male plug at one end is threaded in shaft 178 andexits between adjacent legs 184 under the annular skirt portion of base180.

Referring now to FIG. 3, it will be seen that ball and socket fixture 39includes a socket 40 and a cap 56. Socket 40 is provided with aninternally threaded tapered end section 42 which is turned onto theexternally threaded end of shaft 34. The opposite end of socket 40 isexternally threaded and is formed with a spherical chamber 44. One endof chamber 44 is opened and the other end is formed with an annularshoulder 46. A resilient member 48, for example a helical tensionspring, rests on shoulder 46 and extends axially in chamber 44. A seat50 is interposed between spring 48 and a ball 52 having an extendingshaft 54. Cap 56 is internally threaded and is formed with a seatportion 57 having a concentric through hole 58. Cap 56 is turned ontothe externally threaded section of socket 40. in consequence, seat 50isurged against ball 52, ball 52 is pressed into seat portion57,andshaft 54 extends through hole 58. It will beappreciated that ball 52is universally pivoted within seat 50 and socket 57. The free end ofshaft 54 is attached to a lamp receptacle 60. From the foregoingdescription, it will be apparent that lamp provides a relativelyunlimited degree of adjustment, i.e. shaft 34 is rotatable and slidablewithin sleeve 18 and receptacle 60 is universally pivoted with respectto shaft 34.

Lamp receptacle 60 includes a forward section 62 and a rearward section64. Rearward section 64 is formed with an annular flange 66 which isadapted to receive shaft 54. A fastener 68, for example a set screw,

- is turned into a threaded hole in flange 66 and engages shaft 54,whereby shaft 54 is secured within flange 66. The forward end ofrearward section 64 is provided with an annularrib 72 and the rearwardend of forward section 62 is externally threaded. An internally threadedring 74 having a rearward annular shoulder portion 76 adapted to engagerib 72 is turned onto the externally threaded rearward end of forwardsection 62. In consequence, forward section 62 and rearward section 64are fastened together by ring 74. The forward end of forward section 62is externally threaded and is adapted to receive an internally threadedflange 78 of a dome shaped shade 80. Mounted within forward section 62is a variable intensity control 82.

Referring now to the schematic diagram illustrated in FIG. 5, it will beseen that variable intensity control 82 includes a variable impedance84, for example, a potentiometer having a wiper arm 86 which isoperatively connected to a control knob 88 via an insulating rod 89.Knob 88 is connected also to the contact arm of a switch 90. One side ofpotentiometer 84 is connected to a lead 92 of a powercord 94 and aterminal 96 of switch 90 is connected to a lead 98 of power cord 94. Aterminal 100 of switch 90 is connected to a terminal 102 of a socket 104and the other side of potentiometer 84. Wiper arm 86 is connected to aterminal 106 of socket 104. Power cord 94 is threaded in an annularguide 108 which is mounted to interior face of leg 38 and exists fromlamp 10 through an aperture in sleeve 18 which is provided with aannular bushing 110 composed of a linear polyamide resin, for example.As shown in FIG. 1 at 111, power cord 94 is spiraled within sleeve 18.in conventional manner, a line plug 112 is attached to the free end ofpower cord 94. Receptacle 60 is adapted to receive socket 104 and socket104 is adapted to receive an incandescent lamp 114, forward section 62being formed with an aperture 113 through which insulating rod 89projects. The intensity of the luminance emitted from lamp 114 isgoverned by the position of wiper arm 86 which is controlled by therotation of knob 88. By way of example, when knob 82 is rotated to itsmost counterclockwise position the intensity of the luminance emittedfrom lamp 114 is greatest, and when knob 82 is rotated to its mostclockwise position the contact between terminals 96 and 100 is brokenand lamp 114 is off.

it is preferred that base 12, shaft 18, bushing 30, shaft 34, ball andsocket fixture 39, receptacle 60, and shade are composed of a metal suchas brass, for example, and insulating rod 89 is composed of a linearpolyamide resin.

It is to be understood that, in alternative embodiments, sleeve 18 andshaft 34 are integral and lamp 10 is not vertically adjustable. Also,the integral sleeve and shaft is swiveled to base 12.

ln- -a second embodiment of the invention shown in FIG. 6, a lamp 116comprises a base 118, a sleeve 120, a straight shaft 122, a swivelfixture 124, a ball and socket fixture 126, a receptacle 128, a variableintensity control 130, a power cord 132, and a shade 134. Base 118,sleeve 120', ball and socket fixture 126, receptacle 128, variableintensity control 130, power cord 132 and shade 134 correspond to base12, sleeve 18, ball and socket fixture 39, receptacle 60, variableintensity control 82, power cord 94, and shade 80, respectively. Bentshaft 34 is replaced by straight shaft 122 and swivel fixture 124. Oneend of shaft 122 is bifurcated and operates in the same manner as thebifurcated end of shaft 34. The other end of shaftl22 is externallythreaded. Swivel fixture 124 includes an offset arm 136 and asubstantially straight arm 138. One end of arm 136 is provided with aninternally threaded cap flange 140 which is turned onto the threaded endof shaft 122. One end of arm 138 is externally threaded and is turnedinto ball and socket fixture 126. The other end of arms 136 and 138 areconnected together by means of a limited swivel joint fitting 142, arms136 and 138 being constrained for limited swiveling movement withrespect to each other.

Referring now to FIG. 7, there is shown at 144 a third embodiment of theinvention. Lamp 144 comprises a base 146, a sleeve 148, a shaft 150, aflexible jointed arm 152, a ball and socket fixture 154, a receptacle156, a variable intensity control 158, a power cord 160, and a shade162. Base 146, sleeve 148, shaft 150, ball and socket fixture 154,receptacle 156, variable intensity control 158, power cord 160, andshade 162 correspond to base 118, sleeve 120, shaft 122, ball andsocketfixture 126, receptacle 128, variable intensity control 130, power cord132, and shade 134, respectively. Flexible jointed arm 152 comprises aplurality of sections 164 which define a convoluted spiralconfiguration. Adjacent sections 164 are slidably intercon nected bymeans of flanges 166 in order to permit bending of flexible jointed arm152 into selected shapes and retention of the selected shape. It is tobe understood that, in alternative embodiments, lamp 144 is notvertically adjustable and arm 152 is mounted to sleeve 148.

Since certain changes may be made in the foregoing disclosure withoutdeparting from the scope of the invention herein involved, it isintended that all matter contained in the above description and depictedin the accompanying drawings be construed in an illustrative and not ina limiting sense.

What is claimed is:

1. A multiple position, variable intensity lamp comprising:

a. a base;

b. support means having first and second ends, said second endoperatively connected to said support means, said first end operativelyconnected to said base;

c. receptacle means universally pivoted to said support means secondend;

. socket means having at least first and second terminals mounted withinsaid receptacle-means, said socket means adapted receive at least oneincandescent lamp;

e. variable intensity means operatively mounted within said receptaclemeans and electrically connected to said socket means, said variableintensity means operating to control the intensity of luminance emittedby said incandescent lamp;

f. cord means having at least first and second leads electricallyconnected to said variable intensity means for applying electrical powerto said variable intensity means; and

g. a swivel fixture, said swivel fixture having an offset prising:

a. a base;

b. support means having first and second ends, said second endoperatively connected to said support means and said first endoperatively connected to said base;

c. receptacle means universally pivoted to said support means secondend;

. socket means having at least first and second terminals mounted withinsaid receptacle means, said socket means adapted to receive at least oneincandescent lamp;

e. variable intensity means operatively mounted within said receptaclemeans and electrically connected to said socket means, said variableintensity means operating to control the intensity of luminance emittedby said incandescent lamp;

f. cord means having at least first and second leads electricallyconnected to said variable intensity means for applying electrical powerto said variable intensity means; and

g. a flexible jointed arm interposed between said support means andreceptacle means, said flexible jointed arm having a plurality ofsections defining a convoluted spiral configuration, adjacent sectionsslidably interconnected by means of flanges operating to permit bendingof said flexible jointed arm into selected shapes and retention of theselected shape.

3. A multiple position, variable intensity lamp comprising:

a. a base;

b. support means having first and second ends, said second endoperatively connected to said support means and said first endoperatively connected to said base;

0. receptacle means universally pivoted to said support means secondend;

d. socket means having at least first and second terminals mountedwithin said receptacle means, said socket means adapted receive at leastone incandescent lamp;

e. variable intensity means operatively mounted within said receptaclemeans and electrically connected to said socket means, said variableintensity means operating to control the intensity of luminance emittedby said incandescent lamp; and

f. cord means having at least first and second leads electricallyconnected to said variable intensity means for applying electrical powerto said variable intensity means;

g. said variable intensity means including variable impedance means andswitch means, said variable impedance means including a potentiometerhaving a wiper arm, said switch means having at least first and secondterminal means, one side of said potentiometer connected to said firstlead, the other side of said potentiometer connected said first terminalmeans of said switch means, said second terminal means of said switchmeans connected to said second lead, said wiper arm connected to saidsecond terminal of said socket means, said switch means having engagedand disengaged positions, said first and second terminal means of saidswitch means being electrically connected when said switch means isengaged, said first and second terminal means of said switch means beingelectrically disconnected when said switch means is disengaged,electrical power being applied to said socket means when said switchmeans is engaged, luminance being emitted from said incandescent lampwhen said switch means is engaged, the position of said wiper armoperating to control the intensity of the luminance emitted from saidincandescent lamp when said switch means is engaged.

4.'The lamp as claimed in claim 3 including insulating rod means andknob, said rod means operatively connected to said wiper arm and switchmeans, said knob connected to said rod means, said wiper arm and switchmeans being responsive to rotational movement of said rod means, saidswitch means being disengaged when said rod means is rotated to its mostclockwise position.

5. A multiple position, variable intensity lamp comprising:

a. a base; I

b. a sleeve operatively connected to said base;

c. a shaft bifurcated at one end, said shaft received within saidsleeve, the bifurcated end of said shaft defining a pair of outwardlydiverging legs which operate to engage the interior wall of said sleeve,the engagement of said legs and interior wall operating as a frictionallock;

receptacle means universally pivotable with respect to said shaft;

e. socket means having at least first and second ter minals mountedwithin said receptacle means, said socket means adapted to receive atleast one incandescent lamp;

f. variable impedance means having a wiper arm, said variable impedancemeans mounted within said receptacle means and operatively connected tosaid socket means;

g. Switch means having at leastfirst and second terminals mounted withinsaid receptacle means and electrically connected to said socket means;

cord means having at least first and second leads for applyingelectrical power to said incandescent lamp, said first lead electricallyconnected to one side of said variable impedance means, the other sideof said variable impedance means connected to said first terminal ofsaid switch means and said first terminal of said socket means, saidsecond lead connected to said second terminal of said switch means;

i. said switch means having engaged and disengaged positions, theelectrical power being applied to said socket means when said switchmeans is engaged, luminance emitted from said incandescent lamp whensaid switch means is engaged, the intensity of luminance emitted fromsaid incandescent lamp governed by the position of said wiper arm.

6. The lamp as claimed in claim 5 including a swivel fixture, saidswivel fixture having an ofi'set arm and a substantially straight arm,one endof said offset arm connected to the other end of said shaft, oneend of said straight arm operatively connected to said receptacle means,the other ends of each said arm connected together by means of a limitedswivel joint fitting, said arms being constrained for limited swivelingmovement with respect to each other.

7. The lamp as claimed in claim 5 including a flexible jointed arminterposed between said shaft and receptacle means, said flexiblejointed arm having a plurality of sections defining a convoluted spiralconfiguration, adjacent sections slidably interconnected by means offlanges operating to permit bending of said flexible jointed arm intoselected shapes and retention of the selected shape.

8. The lamp as claimed in claim 5 wherein said cord means is spiraledwithin said sleeve.

1. A multiple position, variable intensity lamp comprising: a. a base;b. support means having first and second ends, said second endoperatively connected to said support means, said first end operativelyconnected to said base; c. receptacle means universally pivoted to saidsupport means second end; d. socket means having at least first andsecond terminals mounted within said receptacle means, said socket meansadapted receive at least one incandescent lamp; e. variable intensitymeans operatively mounted within said receptacle means and electricallyconnected to said socket means, said variable intensity means operatingto control the intensity of luminance emitted by said incandescent lamp;f. cord means having at least first and second leads electricallyconnected to said variable intensity means for applying electrical powerto said variable intensity means; and g. a swivel fixture, said swivelfixture having an offset arm and a substantially straight arm, one endof said offset arm connected to end of said support means second end,one end of said straight arm operatively connected to said receptaclemeans, the other ends of each said arm connected together by means of alimited swivel joint fitting, said arms being constrained for limitedswiveling movement with respect to each other
 2. A multiple position,variable intensity lamp comprising: a. a base; b. support means havingfirst and second ends, said second end operatively connected to saidsupport means and said first end operatively connected to said base; c.receptacle means universally pivoted to said support means second end;d. socket means having at least first and second terminals mountedwithin said receptacle means, said socket means adapted to receive atleast one incandescent lamp; e. variable intensity means operativelymounted within said receptacle means and electrically connEcted to saidsocket means, said variable intensity means operating to control theintensity of luminance emitted by said incandescent lamp; f. cord meanshaving at least first and second leads electrically connected to saidvariable intensity means for applying electrical power to said variableintensity means; and g. a flexible jointed arm interposed between saidsupport means and receptacle means, said flexible jointed arm having aplurality of sections defining a convoluted spiral configuration,adjacent sections slidably interconnected by means of flanges operatingto permit bending of said flexible jointed arm into selected shapes andretention of the selected shape.
 3. A multiple position, variableintensity lamp comprising: a. a base; b. support means having first andsecond ends, said second end operatively connected to said support meansand said first end operatively connected to said base; c. receptaclemeans universally pivoted to said support means second end; d. socketmeans having at least first and second terminals mounted within saidreceptacle means, said socket means adapted receive at least oneincandescent lamp; e. variable intensity means operatively mountedwithin said receptacle means and electrically connected to said socketmeans, said variable intensity means operating to control the intensityof luminance emitted by said incandescent lamp; and f. cord means havingat least first and second leads electrically connected to said variableintensity means for applying electrical power to said variable intensitymeans; g. said variable intensity means including variable impedancemeans and switch means, said variable impedance means including apotentiometer having a wiper arm, said switch means having at leastfirst and second terminal means, one side of said potentiometerconnected to said first lead, the other side of said potentiometerconnected said first terminal means of said switch means, said secondterminal means of said switch means connected to said second lead, saidwiper arm connected to said second terminal of said socket means, saidswitch means having engaged and disengaged positions, said first andsecond terminal means of said switch means being electrically connectedwhen said switch means is engaged, said first and second terminal meansof said switch means being electrically disconnected when said switchmeans is disengaged, electrical power being applied to said socket meanswhen said switch means is engaged, luminance being emitted from saidincandescent lamp when said switch means is engaged, the position ofsaid wiper arm operating to control the intensity of the luminanceemitted from said incandescent lamp when said switch means is engaged.4. The lamp as claimed in claim 3 including insulating rod means andknob, said rod means operatively connected to said wiper arm and switchmeans, said knob connected to said rod means, said wiper arm and switchmeans being responsive to rotational movement of said rod means, saidswitch means being disengaged when said rod means is rotated to its mostclockwise position.
 5. A multiple position, variable intensity lampcomprising: a. a base; b. a sleeve operatively connected to said base;c. a shaft bifurcated at one end, said shaft received within saidsleeve, the bifurcated end of said shaft defining a pair of outwardlydiverging legs which operate to engage the interior wall of said sleeve,the engagement of said legs and interior wall operating as a frictionallock; d. receptacle means universally pivotable with respect to saidshaft; e. socket means having at least first and second terminalsmounted within said receptacle means, said socket means adapted toreceive at least one incandescent lamp; f. variable impedance meanshaving a wiper arm, said variable impedance means mounted within saidreceptacle means and operatively connected to said socket means; g.switch means having at least First and second terminals mounted withinsaid receptacle means and electrically connected to said socket means;h. cord means having at least first and second leads for applyingelectrical power to said incandescent lamp, said first lead electricallyconnected to one side of said variable impedance means, the other sideof said variable impedance means connected to said first terminal ofsaid switch means and said first terminal of said socket means, saidsecond lead connected to said second terminal of said switch means; i.said switch means having engaged and disengaged positions, theelectrical power being applied to said socket means when said switchmeans is engaged, luminance emitted from said incandescent lamp whensaid switch means is engaged, the intensity of luminance emitted fromsaid incandescent lamp governed by the position of said wiper arm. 6.The lamp as claimed in claim 5 including a swivel fixture, said swivelfixture having an offset arm and a substantially straight arm, one endof said offset arm connected to the other end of said shaft, one end ofsaid straight arm operatively connected to said receptacle means, theother ends of each said arm connected together by means of a limitedswivel joint fitting, said arms being constrained for limited swivelingmovement with respect to each other.
 7. The lamp as claimed in claim 5including a flexible jointed arm interposed between said shaft andreceptacle means, said flexible jointed arm having a plurality ofsections defining a convoluted spiral configuration, adjacent sectionsslidably interconnected by means of flanges operating to permit bendingof said flexible jointed arm into selected shapes and retention of theselected shape.
 8. The lamp as claimed in claim 5 wherein said cordmeans is spiraled within said sleeve.